Can a Pakistani tourist in Thailand apply for a medical visa without returning to Pakistan?

This question is for a Pakistani friend. She is currently in Thailand on a tourist visa that expires January 2 and eligible for 7 day extension. She has a skin problem mainly on her lower legs and feet that did not respond to treatment in Pakistan. It's not life threatening that it severely affects her ability to fly, but it is not a minor condition either. She would like to stay longer and see if she can get that treated. Does anyone know if she can get a medical visa without having to return to Pakistan and if so what documents/requirements she would need? Thanks.